Mobile communication of Long Term Evolution (LTE), LTE-advanced, and the like is conventionally known. Further, techniques of using shared band such as unlicensed band (Unlicensed band) is being studied (for example, refer to Published Japanese-Translations of PCT Applications, Publication Nos. 2013-523018 and 2008-518541, and Japanese Laid-Open Patent Publication Nos. 2006-203361 and 2007-312078).